Asign Computer Name And Join Them to a domain in a UA windows xp insta

[fullmetal_ARM]

hi i want to install windows xp on 20 workstation in a friend's company. In the unattended installation i want all the computer to have a different unique computer name like WS-1, WS-2, ...... and then join to a domain.

How can i do this.

What entries can i set in the winnt.sif file.?